Nano-Ni-Induced Electronic Modulation of MoS₂ Nanosheets Enables Energy-Saving H₂ Production and Sulfide Degradation

Electrocatalytic hydrogen evolution and sulfion (S2-) recycling are promising strategies for boosting H-2 production and removing environmental pollutants. Here, a nano-Ni-functionalized molybdenum disulfide (MoS2) nanosheet was assembled on steel mesh (Ni-MoS2/SM) for use in sulfide oxidation reaction-assisted, energy-saving H-2 production. Experimental and theoretical calculation results revealed that anchoring nano-Ni on high-surface-area slack MoS2 nanosheets not only optimized catalyst adsorption of polysulfides but also played an important role in promoting hydrogen evolution reaction kinetics by absorbing OHad, thereby greatly enhancing the catalytic performance toward sulfide oxidation reaction and hydrogen evolution reaction. Meanwhile, the Ni/MoS2-based hydrogen evolution reaction + sulfide oxidation reaction system achieved nearly 100% hydrogen production efficiency and only consumed 61% less power per kWh than the oxygen evolution reaction + hydrogen evolution reaction system, which suggested our proposed Ni-MoS2 and novel hydrogen production system are promising for sustainable energy production.